SA575 Low Voltage Compandor The SA575 is a precision dual gain control circuit designed for low voltage applications. The SA575's channel 1 is an expandor, while channel 2 can be configured either for expandor, compressor, or automatic level controller (ALC) application. Features http://onsemi.com * Operating Voltage Range from 3.0 V to 7.0 V * Reference Voltage of 100 mVRMS = 0 dB * One Dedicated Summing Op Amp Per Channel and Two Extra * * * * SOIC-20 WB D SUFFIX CASE 751D 20 Uncommitted Op Amps 600 Drive Capability Single or Split Supply Operation Wide Input/Output Swing Capability Pb-Free Packages are Available* 1 TSSOP-20 DTB SUFFIX CASE 948E 20 Applications * * * * * * * * * Portable Communications Cellular Radio Cordless Telephone Consumer Audio Portable Broadcast Mixers Wireless Microphones Modems Electric Organs Hearing Aids 1 PDIP-20 N SUFFIX CASE 738 20 1 PIN CONNECTIONS D* and DTB Packages +VIN1 1 20 VCC -VIN1 2 19 +VIN2 VOUT1 3 18 -VIN2 RECT. IN1 4 17 VOUT2 CRECT1 5 16 RECT.IN2 SUM OUT 1 6 15 CRECT2 COMP. IN1 7 14 SUM OUT2 VREF 8 GAIN CELL IN1 9 GND 10 13 COMP.IN2 12 SUM NODE 2 11 GAIN CELL IN2 *Available in large SOL package only. ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 13 of this data sheet. *For additional information on our Pb-Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. (c) Semiconductor Components Industries, LLC, 2006 September, 2006 - Rev. 3 1 DEVICE MARKING INFORMATION See general marking information in the device marking section on page 13 of this data sheet. Publication Order Number: SA575/D SA575 0.1F VCC +5V C15 1 + 2 - 575 3 + + 19 - 18 OP AMP 10F 4 C14 VREF 10k 17 C11 5 CRECT 2.2F VIN + R13 3.8k + GND 10F 20 OP AMP C3 VOUT VCC + 16 4.7F 3.8k 6 C10 CRECT 15 + + 2.2F GND C6 VIN 10F 7 14 10k + 8 VREF 10F 9 R7 12 G 10k G 11 PIN FUNCTION DESCRIPTION Symbol 1 +VIN1 Non-Inverted Input 1 2 -VIN1 Inverted Input 1 3 VOUT Output 4 RECT. IN1 5 CRECT1 6 SUM OUT1 Summation Output 1 7 COMP. IN1 Compensator Pin 8 VREF Voltage Reference 9 GAIN CELL IN1 10 GND Description Rectifier 1 Input External Capacitor Pinout for Rectifier 1 Variable Gain Cell Input 1 Ground 11 GAIN CELL IN2 12 SUM NODE 2 13 COMP. IN2 Compensator Pin 14 SUM OUT2 Summation Output 2 15 CRECT2 16 RECT. IN2 17 VOUT2 Output 2 18 -VIN2 Inverted Input 2 19 +VIN2 Non-Inverted Input 2 20 VCC 1F GND Figure 1. Block Diagram and Test Circuit Pin C8 10k GND GND + 30k 10 GND R8 30k 13 VREF 10k + 10F Variable Gain Cell Input 2 Summation Node 2 External Capacitor Pinout for Rectifier 2 Rectifier 2 Input Positive Power Supply http://onsemi.com 2 VOUT SA575 MAXIMUM RATINGS Symbol Value Unit Single Supply Voltage Rating VCC -0.3 to 8.0 V Voltage Applied to Any Other Pin VIN -0.3 to (VCC + 0.3) V Operating Ambient Temperature Range TA -40 to +85 C Operating Junction Temperature TJ 150 C TSTG 150 C Storage Temperature Range Thermal Impedance SOIC TSSOP PDIP JA 87 124 70 C/W Maximum Power Dissipation SOIC TSSOP PDIP PD 1116 1068 1344 mW Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected. DC ELECTRICAL CHARACTERISTICS Typical values are at TA = 25C. Minimum and Maximum values are for the full operating temperature range: -40 to +85C for SA575, except SSOP package is tested at +25C only. VCC = 5.0 V, unless otherwise stated. Both channels are tested in the Expandor mode (see Test Circuit). Characteristic Symbol Test Conditions Min Typ Max Unit FOR COMPANDOR, INCLUDING SUMMING AMPLIFIER Supply Voltage (Note 1) VCC - 3.0 5.0 7.0 V Supply Current ICC No Signal 3.0 4.2 5.5 mA Reference Voltage (Note 2) VREF VCC = 5.0 V 2.4 2.5 2.6 V Summing Amp Output Load RL - 10 - - k Total Harmonic Distortion THD 1.0 kHz, 0 dB, BW = 3.5 kHz - 0.12 1.5 % Output Voltage Noise ENO BW = 20 kHz, RS = 0 - 6.0 30 V Unity Gain Level 0dB 1.0 kHz -1.5 - 1.5 dB Output Voltage Offset VOS No Signal -150 - 150 mV Output DC Shift No Signal to 0 dB -100 - 100 mV Gain Cell Input = 0 dB, 1.0 kHz Rectifier Input = 6.0 dB, 1.0 kHz -1.0 - 1.0 dB Gain Cell Input = 0 dB, 1.0 kHz Rectifier Input = -30 dB, 1.0 kHz -1.0 - 1.0 dB 1.0 kHz, 0 dB, CREF = 220 F - -80 -65 dB VO RL = 10 k VCC-0.4 VCC - V RL 1.0 kHz 600 - - CMR - 0 - VCC V Tracking Error Relative to 0 dB Crosstalk FOR OPERATIONAL AMPLIFIER Output Swing Output Load Input Common-Mode Range Common-Mode Rejection Ratio Input Bias Current CMRR - 60 80 - dB IB VIN = 0.5 V to 4.5 V -1.0 - 1.0 A Input Offset Voltage VOS - - 3.0 - mV Open-Loop Gain AVOL RL = 10 k - 80 - dB Slew Rate SR Unity Gain - 1.0 - V/s Bandwidth GBW Unity Gain - 3.0 - MHz ENI BW = 20 kHz - 2.5 - V PSRR 1.0 kHz, 250 mV - 60 - dB Input Voltage Noise Power Supply Rejection Ratio 1. Operation down to VCC = 2.0 V is possible, but performance is reduced. See curves in Figures 6 and 7. 2. Reference voltage, VREF, is typically at 1/2 VCC. http://onsemi.com 3 SA575 Functional Description C6 is for decoupling and stabilizing the voltage reference circuit. The value of C6 should be such that it will offer a very low impedance to the lowest frequencies of interest. Too small a capacitor will allow supply ripple to modulate the audio path. The better filtered the power supply, the smaller this capacitor can be. R12 provides DC reference voltage to the amplifier of channel B. R6 and R7 provide a DC feedback path for the summing amp of channel B, while C7 is a short-circuit to ground for signals. C14 and C15 are for power supply decoupling. C14 can also be eliminated if the power supply is well regulated with very low noise and ripple. This section describes the basic subsystems and applications of the SA575 Compandor. More theory of operation on compandors can be found in AND8159 and AND8160. The typical applications of the SA575 low voltage compandor in an Expandor (1:2), Compressor (2:1) and Automatic Level Control (ALC) function are explained. These three circuit configurations are shown in Figures 2, 3, and 4 respectively. The SA575 has two channels for a complete companding system. The left channel, A, can be configured as a 1:2 Expandor while the right channel, B, can be configured as either a 2:1 Compressor, a 1:2 Expandor or an ALC. Each channel consists of the basic companding building blocks of rectifier cell, variable gain cell, summing amplifier and VREF cell. In addition, the SA575 has two additional high performance uncommitted op amps which can be utilized for application such as filtering, pre-emphasis/ de-emphasis or buffering. Figure 5 shows the complete schematic for the applications demo board. Channel A is configured as an expandor while channel B is configured so that it can be used either as a compressor or as an ALC circuit. The switch, S1, toggles the circuit between compressor and ALC mode. Jumpers J1 and J2 can be used to either include the additional op amps for signal conditioning or exclude them from the signal path. Bread boarding space is provided for R1, R2, C1, C2, R10, R11, C10 and C11 so that the response can be tailored for each individual need. The components as specified are suitable for the complete audio spectrum from 20 Hz to 20 kHz. The most common configuration is as a unity gain non-inverting buffer where R1, C1, C2, R10, C10 and C11 are eliminated and R2 and R11 are shorted. Capacitors C3, C5, C8, and C12 are for DC blocking. In systems where the inputs and outputs are AC coupled, these capacitors and resistors can be eliminated. Capacitors C4 and C9 are for setting the attack and release time constant. Demonstrated Performance The applications demo board was built and tested for a frequency range of 20 Hz to 20 kHz with the component values as shown in Figure 5 and VCC = 5.0 V. In the expandor mode, the typical input dynamic range was from -34 dB to +12 dB where 0 dB is equal to 100 mVRMS. The typical unity gain level measured at 0 dB @ 1.0 kHz input was "0.5 dB and the typical tracking error was "0.1 dB for input range of -30 to +10 dB. In the compressor mode, the typical input dynamic range was from -42 dB to "18 dB with a tracking error +0.1 dB and the typical unity gain level was "0.5 dB. In the ALC mode, the typical input dynamic range was from -42 dB to +8.0 dB with typical output deviation of "0.2 dB about the nominal output of 0 dB. For input greater than +9.0 dB in ALC configuration, the summing amplifier sometimes exhibits high frequency oscillations. There are several solutions to this problem. The first is to lower the values of R6 and R7 to 20 k each. The second is to add a current limiting resistor in series with C12 at Pin 13. The third is to add a compensating capacitor of about 22 to 30 pF between the input and output of summing amplifier (Pins 12 and 14). With any one of the above recommendations, the typical ALC mode input range increased to +18 dB yielding a dynamic range of over 60 dB. http://onsemi.com 4 SA575 Expandor accuracy of the gain cell. This can be improved by using an extra capacitor from the input to Pin 4 and eliminating the DC connection between Pins 4 and 9. The expandor gain expression and the attack and release time constant is given by Equation 1 and Equation 2, respectively. The typical expandor configuration is shown in Figure 2. The variable gain cell and the rectifier cell are in the signal input path. The VREF is always 1/2 VCC to provide the maximum headroom without clipping. The 0 dB ref is 100 mVRMS. The input is AC coupled through C5, and the output is AC coupled through C3. If in a system the inputs and outputs are AC coupled, then C3 and C5 can be eliminated, thus requiring only one external component, C4. The variable gain cell and rectifier cell are DC coupled so any offset voltage between Pins 4 and 9 will cause small offset error current in the rectifier cell. This will affect the Expandor gain = 4VIN(avg) 3.8 k x 100 A 2 where VIN(avg) = 0.95VIN(RMS) R = A = 10 k x CRECT = 10 k x C4 7, 13 C5 10k 9, 11 EXP IN G 10k 10F 6, 14 C3 EXP OUT 10F 4, 16 3.8k 5, 15 C4 (eq. 1) 8 2.2F VREF Figure 2. Typical Expandor Configuration http://onsemi.com 5 (eq. 2) SA575 Compressor the output to input. In the presence of an AC signal this phenomenon is not observed and the circuit will appear to function properly. The compressor gain expression and the attack and release time constant is given by Equation 3 and Equation 4, respectively. The typical compressor configuration is shown in Figure 3. In this mode, the rectifier cell and variable gain cell are in the feedback path. R6 and R7 provide the DC feedback to the summing amplifier. The input is AC coupled through C12 and output is AC coupled through C8. In a system with inputs and outputs AC coupled, C8 and C12 could be eliminated and only R6, R7, C7, and C13 would be required. If the external components R6, R7 and C7 are eliminated, then the output of the summing amplifier will motor-boat in absence of signals or at extremely low signals. This is because there is no DC feedback path from Compressor gain = 3.8 k x 100 A 1/2 4VIN(avg) where VIN(avg) = 0.95VIN(RMS) R = A = 10 k x CRECT = 10 k x C4 R6 R7 30k 30k 1F C7 VREF 8 12 C8 C12 14 COMP OUT 13 10F COMP IN 10F 10k 11 G 10k 16 3.8k C13 4.7F 15 C9 (eq. 3) 2.2F Figure 3. Typical Compressor Configuration http://onsemi.com 6 (eq. 4) SA575 Automatic Level Control absence of signals. CCOMP is necessary to stabilize the summing amplifier at higher input levels. This circuit provides an input dynamic range greater than 60 dB with the output within "0.5 dB typical. The necessary design expressions are given by Equation 5 and Equation 6, respectively. The typical Automatic Level Control circuit configuration is shown in Figure 4. It can be seen that it is quite similar to the compressor schematic except that the input to the rectifier cell is from the input path and not from the feedback path. The input is AC coupled through C12 and C13 and the output is AC coupled through C8. Once again, as in the previous cases, if the system input and output signals are already AC coupled, then C12, C13 and C8 could be eliminated. Concerning the compressor, removing R6, R7 and C7 will cause motor-boating in ALC gain = 3.8 k x 100 A (eq. 5) 4VIN(avg) R = A = 10 k x CRECT = 10 k x C9 R6 R7 30k 30k 1F C7 C COMP VREF 22pF 8 12 C12 C8 14 13 ALC IN 10k 10F 11 G 10k C13 16 4.7F ALC OUT 10F 3.8k 15 C9 2.2F Figure 4. Typical ALC Configuration http://onsemi.com 7 (eq. 6) SA575 VCC -5V C15 VREF 0.1F C14 1 + 575 VCC R1 2 C1 C2 - R2 19 - 18 OP AMP 16 3.8k C4 6 C5 EXP IN J2 C13 5 2.2F C11 17 3.8k ALC 4.7F S1 C9 COMP 15 2.2F 7 14 C8 10k 10F 8 VREF 13 VREF 10k C6 10F 9 COMP/ ALC IN C10 R11 4 10F C12 10F R10 C3 J1 + R12 10k 47F OP AMP 3 EXP OUT 20 R6 12 G 10k G 10 R7 30k 30k 11 10k GND Figure 5. SA575 Low Voltage Expandor/Compressor/ALC Demo Board http://onsemi.com 8 10F C7 1F COMP/ ALC OUT SA575 1.0 0.9 0.8 0.7 0.6 UNITY GAIN ERROR (dB) 0.5 0.4 0.3 0.2 VCC 7V 0.1 0.0 VCC 5V -0.1 -0.2 -0.3 VCC 3V -0.4 -0.5 VCC 2V -0.6 -0.7 -0.8 -0.9 -1.0 -50 -25 0 25 50 75 100 TEMPERATURE (C) Figure 6. Unity Gain Error vs. Temperature and VCC 4.4 4.2 4.0 (mA) I CC VCC 7V 3.8 3.6 VCC 5V 3.4 VCC 3V VCC 2V 3.2 3.0 -50 -25 0 25 50 TEMPERATURE (C) Figure 7. ICC vs. Temperature and VCC http://onsemi.com 9 75 100 SA575 TYPICAL PERFORMANCE CHARACTERISTICS 8 GENERAL DIAGRAM 4.7F 10F 6 10dB IN INPUT (20-20kHz) 4 G REC SUM OUTPUT 2 0dB IN VCC = 5V 0 OUTPUT LEVEL (dB) -2 -4 -6 -8 -10 -12 -14 -16 -18 -40dB IN -20 -22 10 100 1000 10000 30000 FREQUENCY (Hz) Figure 8. Compressor Output Frequency Response http://onsemi.com 10 SA575 TYPICAL PERFORMANCE CHARACTERISTICS 8 INPUT (20-20kHz) 6 GENERAL DIAGRAM 2.5dB IN 4.7F REC 4 OUTPUT SUM 2 G 0dB IN 10F VCC = 5V 0 OUTPUT LEVEL (dB) -2 -4 -6 -8 -10 -12 -14 -16 -18 -10dB IN -20 -22 10 100 1000 10000 FREQUENCY (Hz) Figure 9. Expandor Output Frequency Response http://onsemi.com 11 30000 SA575 COMPRESSOR IN EXPANDOR OUT +10dB +10dB +5dB 0dB 100mV 100mV 0dB 0dB -5dB -10dB -10dB -10dB -15dB -20dB -20dB -20dB -25dB -30dB -30dB -40dB -40dB -50dB -50dB } } COMPRESSION EXPANSION Figure 10. The Companding Function http://onsemi.com 12 SA575 ORDERING INFORMATION Package Temperature Range Shipping SA575D SOIC-20 WB -40 to +85C 38 Units / Rail SA575DR2 SOIC-20 WB -40 to +85C 1000 / Tape & Reel SA575DR2G SOIC-20 WB (Pb-Free) -40 to +85C 1000 / Tape & Reel SA575DTB TSSOP-20* -40 to +85C 75 Units / Rail SA575DTBR2 TSSOP-20* -40 to +85C 2500 Tape & Reel PDIP-20 -40 to +85C 18 Units / Rail Device SA575N For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specification Brochure, BRD8011/D. *This package is inherently Pb-Free. MARKING DIAGRAMS SOIC-20 WB D SUFFIX CASE 751D TSSOP-20 DTB SUFFIX CASE 948E SA575D AWLYYWW SA 575 ALYW PDIP-20 N SUFFIX CASE 738 20 1 A WL, L YY, Y WW, W = Assembly Location = Wafer Lot = Year = Work Week http://onsemi.com 13 SA575N AWLYYWW SA575 PACKAGE DIMENSIONS SO-20 WB CASE 751D-05 ISSUE G q A 20 X 45 _ h 1 10 20X B B 0.25 M T A S B S A L H M E 0.25 10X NOTES: 1. DIMENSIONS ARE IN MILLIMETERS. 2. INTERPRET DIMENSIONS AND TOLERANCES PER ASME Y14.5M, 1994. 3. DIMENSIONS D AND E DO NOT INCLUDE MOLD PROTRUSION. 4. MAXIMUM MOLD PROTRUSION 0.15 PER SIDE. 5. DIMENSION B DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE PROTRUSION SHALL BE 0.13 TOTAL IN EXCESS OF B DIMENSION AT MAXIMUM MATERIAL CONDITION. 11 B M D 18X e A1 SEATING PLANE C T http://onsemi.com 14 DIM A A1 B C D E e H h L q MILLIMETERS MIN MAX 2.35 2.65 0.10 0.25 0.35 0.49 0.23 0.32 12.65 12.95 7.40 7.60 1.27 BSC 10.05 10.55 0.25 0.75 0.50 0.90 0_ 7_ SA575 PACKAGE DIMENSIONS TSSOP-20 DTB SUFFIX CASE 948E-02 ISSUE B 20X 0.15 (0.006) T U 2X K REF 0.10 (0.004) S L/2 20 M T U S V S K K1 IIII IIII IIII 11 B L J J1 -U- PIN 1 IDENT SECTION N-N 1 10 0.25 (0.010) N 0.15 (0.006) T U S NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DIMENSION A DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH OR GATE BURRS SHALL NOT EXCEED 0.15 (0.006) PER SIDE. 4. DIMENSION B DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSION. INTERLEAD FLASH OR PROTRUSION SHALL NOT EXCEED 0.25 (0.010) PER SIDE. 5. DIMENSION K DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.08 (0.003) TOTAL IN EXCESS OF THE K DIMENSION AT MAXIMUM MATERIAL CONDITION. 6. TERMINAL NUMBERS ARE SHOWN FOR REFERENCE ONLY. 7. DIMENSION A AND B ARE TO BE DETERMINED AT DATUM PLANE -W-. M A -V- N F DETAIL E -W- C D G H DETAIL E 0.100 (0.004) -T- SEATING PLANE http://onsemi.com 15 DIM A B C D F G H J J1 K K1 L M MILLIMETERS MIN MAX 6.40 6.60 4.30 4.50 --- 1.20 0.05 0.15 0.50 0.75 0.65 BSC 0.27 0.37 0.09 0.20 0.09 0.16 0.19 0.30 0.19 0.25 6.40 BSC 0_ 8_ INCHES MIN MAX 0.252 0.260 0.169 0.177 --- 0.047 0.002 0.006 0.020 0.030 0.026 BSC 0.011 0.015 0.004 0.008 0.004 0.006 0.007 0.012 0.007 0.010 0.252 BSC 0_ 8_ SA575 PACKAGE DIMENSIONS PDIP-20 N SUFFIX CASE 738-03 ISSUE E -A- 20 11 1 10 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION L TO CENTER OF LEAD WHEN FORMED PARALLEL. 4. DIMENSION B DOES NOT INCLUDE MOLD FLASH. B C L -T- K SEATING PLANE M N E G F J D 20 PL 0.25 (0.010) 20 PL 0.25 (0.010) M T A M T B M M DIM A B C D E F G J K L M N INCHES MIN MAX 1.010 1.070 0.240 0.260 0.150 0.180 0.015 0.022 0.050 BSC 0.050 0.070 0.100 BSC 0.008 0.015 0.110 0.140 0.300 BSC 0_ 15_ 0.020 0.040 MILLIMETERS MIN MAX 25.66 27.17 6.10 6.60 3.81 4.57 0.39 0.55 1.27 BSC 1.27 1.77 2.54 BSC 0.21 0.38 2.80 3.55 7.62 BSC 0_ 15_ 0.51 1.01 ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. "Typical" parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including "Typicals" must be validated for each customer application by customer's technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PUBLICATION ORDERING INFORMATION LITERATURE FULFILLMENT: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303-675-2175 or 800-344-3860 Toll Free USA/Canada Fax: 303-675-2176 or 800-344-3867 Toll Free USA/Canada Email: orderlit@onsemi.com N. American Technical Support: 800-282-9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910 Japan Customer Focus Center Phone: 81-3-5773-3850 http://onsemi.com 16 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative SA575/D